Heterostructured MoSe2/Oxygen-Terminated Ti3C2 MXene Architectures for Efficient Electrocatalytic Hydrogen Evolution

Two-dimensional (2D) atomically thin transition metal dichalcogenide MoSe2 has been identified as one of the highly active noble-metal-free catalysts for the electrocatalytic hydrogen evolution reaction (HER), owing to its excellent electronic property and rich active sites. However, the electrocatalytic hydrogen-evolving activity is still hindered by its moderate conductivity, arising from semiconducting property and the thermodynamically stable basal plane. It is anticipated that the integration of 2D MoSe2 nanosheets with a highly conductive large-area 2D substrate enables the accelerated interfacial electron transfer and the enhanced HER performance. We report herein a facile and scalable fabrication of 2D MoSe2/2D Ti3C2 MXene heterostructured architecture, where the layered MoSe2 nanosheets are in situ decorated on the exfoliated oxygen-terminated Ti3C2 MXene flakes. In comparison to pristine MoSe2 and the MoSe2/unmodified Ti3C2 MXene hybrids, the composite electrocatalysts of MoSe2 nanosheets and oxygen-terminated Ti3C2 MXene exhibited improved HER activities, owing to higher electrochemically active surface areas, an oxygen-substituted surface, and the synergy effect between nanosized MoSe2 and oxygen-terminated MXene nanosheets. This study serves to promote continuous efforts toward low-cost, high-performance HER electrocatalysts by taking advantage of merits of transition metal dichalcogenides and 2D nanostructures.